1. Field of the Invention
The present invention relates to a method for preparing 1-methylcyclopropene and applying the same to plants. More specifically, the present invention relates to a method for directly preparing in situ 1-methylcyclopropene, which inhibits the action of ethylene of accelerating the ripening process of plants, wherein the preparation is carried out by reacting a predetermined 1-methylcyclopropene precursor with a base or a fluoride anion material, and applying the 1-methylcyclopropene to plants.
2. Description of the Related Art
Ethylene (C2H4) accelerates the ripening process of plants, while cyclopropene compounds inhibit the action of ethylene in plants [U.S. Pat. No. 5,518,988].
Of these cyclopropene compounds, 1-methylcyclopropene (simply referred to as “1-MCP”) of the following Formula 1 exhibits potent efficacy.

Because 1-MCP is gas even at ambient temperature (b.p: ˜10° C./760 mmHg), it can be easily applied throughout a storage space of agricultural products without any additional spraying device. For this reason, 1-MCP is widely used to store fruits, flowers and vegetables such as apples, pears, persimmons, plums, kiwis, lilies and carnations for a longer time [J. Agric. Food Chem. 53 (2005), 7565˜7570; J. Agric. Food Chem. 51(2003), 4680˜4686; J. Agric. Food Chem. 51(2003), 3858˜3864; J. Agric. Food Chem. 51(2003), 1189˜1200; J. Agric. Food Chem. 47 (1999), 2847˜2853].
However, because most of cyclopropene compounds including 1-MCP are chemically unstable, they can be stored safely only at ultra-low temperature. For this reason, specific methods to store 1-MCP for a long time were developed and utilized in the storage of agricultural products [U.S. Pat. Nos. 6,017,849, 6,426,319, 6,444,619, 6,548,448, 6,762,153 and 6,953,540].
Meanwhile, instead of a method to store chemically unstable 1-MCP, a new attempt to use 1-MCP without storing process at the same time as the preparation was made. For example, the inventor of the present invention suggested a method or device which is capable of applying to plants at the same time as the in situ preparation of cyclopropene compounds including 1-MCP (Korean Patent Application No. 2006-0048121).
This patent discloses preparation of 1-MCP using a variety of chemical reactions and in particular, preparation of cyclopropene compounds by mixing β-halocyclopropylsilane compounds or their chemical equivalents thereof with fluoride ions (F−). Wherein, β-halocyclopropylsilane compounds or their chemical equivalents containing trimethylsilane substitutes (trimethylsilyl, TMS) are the most convenient and economical to prepare.
However, it was newly confirmed that the preparation of cyclopropene compounds from TMS-containing compounds yields fluorotrimethylsilane (Me3SiF) as a by-product which is very harmful to plants as well as human beings. As the result, fluorotrimethylsilane is disadvantageously discharged together with 1-MCP, because its boiling point (16° C./760 mmHg) is very similar to 1-MCP's (˜10° C./760 mmHg). Accordingly, an additional process or device to remove fluorotrimethylsilane is indispensable thereof.